@import url('https://fonts.googleapis.com/css?family=Muli&display=swap');

* {
    box-sizing: border-box;
}

body {
    /* 水平居中 */
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    overflow: hidden;
    font-family: 'Muli','Microsoft YaHei',sans-serif;
    background-image: linear-gradient(to left, #00c6fb 0%, #005bea 100%);
}

.container {
    width: 500px;
}
/* 提示 */
.container h3 {
    margin: 20px 0;
    color: #fff;
    text-align: center;
}
/* 输入栏 */
.container textarea {
    /* 块级元素:独占一行 */
    display: block;
    margin-bottom: 20px;
    padding: 10px;

    width: 100%;
    height: 100px;
    font-family: inherit;
    font-size: 16px;
    border: 0;

}

textarea:focus {
    outline: 0;
}
/* 选项标签 */
.tag {
    /* 改行内块, 一行可以 多个 */
    display: inline-block;
    margin: 0 5px 10px 0;
    padding: 10px 20px;
    color: #fff;
    background-color: orange;
    border-radius: 25px;
}

.tag.highlight {
    opacity: .5;
}